Circular motion question: Mass on a rod rotating in a vertical circle

  • Thread starter Thread starter yusungmagic
  • Start date Start date
  • Tags Tags
    Ball Force Rod
AI Thread Summary
The discussion revolves around understanding the forces acting on a ball attached to a rod rotating in a vertical circle. Participants clarify that the force exerted by the rod on the ball needs to be represented in addition to the gravitational force. There is an emphasis on applying Newton's laws, specifically the relationship between force and acceleration. The direction of the acceleration of the mass is also questioned, highlighting its importance in analyzing the motion. Overall, the conversation aims to clarify the representation of forces in circular motion scenarios.
yusungmagic
Messages
2
Reaction score
0
Homework Statement
A mass is attached to the one end of a rod and made to rotate with constant speed in a vertical circle.
Relevant Equations
Free Body Diagram
By looking at the following question, I have no idea why the direction of force exerted by rod on a ball is represented like that. can anyone help me to understand?
Screenshot 2024-10-24 at 6.44.05 PM.png
 
Physics news on Phys.org
yusungmagic said:
I have no idea why the direction of force exerted by rod on a ball is represented like that.
Like what? The only force I see represented is the weight of the ball. You are asked to add a representation of the force from the rod.
 
sorry for the confusion, you are supposed to draw a force exerted on the mass by the rod. not the "W"
 
yusungmagic said:
sorry for the confusion, you are supposed to draw a force exerted on the mass by the rod. not the "W"
Have faith in Newton's laws! In particular, ##\vec F = m \vec a##
 
yusungmagic said:
sorry for the confusion, you are supposed to draw a force exerted on the mass by the rod. not the "W"
What is the direction of the acceleration of the mass?
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Thread 'Minimum mass of a block'
Here we know that if block B is going to move up or just be at the verge of moving up ##Mg \sin \theta ## will act downwards and maximum static friction will act downwards ## \mu Mg \cos \theta ## Now what im confused by is how will we know " how quickly" block B reaches its maximum static friction value without any numbers, the suggested solution says that when block A is at its maximum extension, then block B will start to move up but with a certain set of values couldn't block A reach...

Similar threads

Replies
5
Views
2K
Replies
7
Views
3K
Replies
31
Views
4K
Replies
8
Views
2K
Back
Top